void setup() {
  Serial.begin(9600);
}

void loop() {
  int val = analogRead(A0);
  float voltage = val * (5.0 / 1023.0); // Assuming default 5V reference
  Serial.print("Raw ADC: ");
  Serial.print(val);
  Serial.print("  -> Voltage: ");
  Serial.println(voltage, 3);
  delay(10000);
}